Thursday, December 30

Reddened skin can be due to thin epidermal layer and lack of pigment as in the case of lips or can be due to conditions like Hemangioma.

Why the skin on the lips is reddened?

Lips appeared reddened because there are plenty of blood vessels in the area.
Further the skin of the lip is very thin and made of three to five cellular layers whereas it is several layers in other areas.
Due to thinness of epidermis in lips the deeper blood vessels give reddened appearance. Further lips have lesser melanin pigment cells.

In infants in the first weeks of life, in some instances, endothelial cells involute to form benign growths (swellings or tumors).
These benign tumors of infancy are called hemangioma and they usually resolve by the age of ten years.

Hemangiomas have blood supply through circulatory system and when they are on the surface of the skin they appear as reddened ripe strawberry.
Hemangiomas are more common in Caucasians and almost ten percent of the population have them.
Further the incidence is three to four times more in female babies when compared to male babies.

The real cause of hemangioma is not known and it is presumed that increased levels of circulating estrogen after childbirth may be the stimulus.
Mostly hemangiomas are uncomplicated and resolve by adolescence.
However they may have a psychological impact on the sufferer, especially when they form on the face.

Rosacea and reddened skin

Rosacea is usually chronic and is characterised by reddened erythema of the face.
Rosacea is a harmless cosmetic concern and to some extent can be treated with anti-inflammatory medicines.
Like hemangioma, rosacea is also affects more women than men.

Rosacea is more common in fair people, especially Caucasians of North and Western European descent.
The usual onset period of rosacea is between thirty to sixty years of age.
Rosacea forming on the face spreads to forehead, nose and cheeks.

Rosacea can also affect to a lesser extent scalp, ears and chest.
Certain conditions like extremes of temperatures, intake of spicy foods and some skin lotions can be triggers and avoiding these triggers and use of sunscreen and anti-inflammatory applications can alleviate the disorder.

Nevus flammeus

Port-wine stain (nevus flammeus) is a birthmark due to superficial and deeper capillaries getting dilated.

Nevus flammeus produces reddened skin discoloration resembling port wine and hence called port-wine stain.
Nevus flammeus is present at birth and usually persists throughout the life of the affected person.

Nevus flammeus are caused by the absence or deficiency of nerve supply in the affected regions causing the blood vessels to dilate and allowing blood to collect in the affected region.
Nevus flammeus, over a period of time, become thickened and develop ridges and bumps and last for the life.
Port-wine stains appear equally on men and women and about 0.3% of the population may be affected by them.

elangiectatic nevus

Telangiectatic nevus, also called as stork bite, salmon patch or angel's kiss, is birthmark having irregular shapes with pink or reddened coloration.
This is a highly prevalent birthmark appearing on the forehead, eyelids, knees, on lips or back of neck.
In telangiectatic nevus, the epidermis is not thickened and feels level with rest of the epidermis.
Stork bite is due to dilation of blood vessels and resolves by itself as the child grows.

In many instances, urticaria is idiopathic and the reasons are unknown.
Urticaria due to allergy usually resolves by about six months and idiopathic urticaria many become chronic.

Palmar erythema and reddened skin

Reddened palms, especially at hypothenar and thenar eminences is called Palmar erythema.
Many diseases and disorders are associated with this condition and notable among them are high blood pressure, liver diseases, thyrotoxicosis, rheumatoid arthritis, eczema and psoriasis.

Wednesday, December 15

There are many causes for yellow skin color and discoloration and the condition has to be evaluated immediately as some are harmless changes, whereas some are due to serious disorders which can be life threatening, requiring immediate treatment.

Causes of yellow skin color

Certain pigments in the food like carotene get deposited in the epidermal layers when in excess and their presence causes yellow skin color change which is harmless.
However, certain disorders of the body systems can interfere with the metabolism of carotene.

These disorders induce carotene deposition and discoloration even though serum levels of carotene are normal, requiring investigation.
The excretion of certain medicines through epidermal layers shows up as yellow skin color.
The buildup of bilirubin in the blood and the onset of jaundice is due to many diseases and disorders leading to yellow coloration.

Jaundice caused yellow skin discoloration

Jaundice (aka icterus) is yellow pigmentation of the dermal and epidermal layers, sclerae (white of eyes) and mucous membranes.
The increased levels of bilirubin in blood plasma (1.5 mg/dL), also known as hyperbilirubinemia, causes jaundice.
Hyperbilirubinemia can be due to various factors and categorized into pre-hepatic, hepatocellular and post-hepatic types.

In hepatocellular jaundice there is usually cholestasis (bile not flowing to duodenum) and the causes are hepatitis of any origin, liver toxicity, genetic disorders like Gilbert's syndrome, alcoholic liver disease and Crigler-Najjar syndrome.

Post-hepatic jaundice is usually due to interruption to the flow of bile inside liver as well as to duodenum.

The causes can be gallstones in the bile duct, cancer of pancreas, obstruction by liver flukes, biliary atresia (passage closed or absent), ductal carcinoma (tumor in the duct), pancreatitis (inflammation of the pancreas) and pancreatic pseudocysts (circumscribed collection of fluid rich in pancreatic enzymes, blood, and necrotic tissue).
Jaundice discoloration conditions require a combination of liver function tests to arrive at the exact causes and diagnosis.

Newborn and yellow skin color

Mild jaundice is observed in many newborns and this neonatal jaundice is usually harmless.
This condition may be seen from second day to eighth day in normal birth and for about two weeks in premature births.
It is presumed that apart from higher turnover of red blood cells, physiological and metabolic adjustments after birth, causes this increase in serum bilirubin in newborn.
This increased levels of bilirubin gets lowered with regular urination and bowel movement; hence regular and proper feeding of the baby are very important.
However in a few rare cases, neonatal hyperbilirubinemia causes kernicterus, a brain-damaging condition, resulting in lifelong disability.

To avoid this risk it is better to treat the neonatal jaundice by exposing the baby to intense photo-therapy.
Inadequate feed, infections, internal bleeding or liver disorder or malfunction or incompatible Rh blood factors of mother and child can also lead to skin discoloration requiring proper treatment.

Primary carotenoderma

Ingesting food containing high levels of carotenoids leads increased serum levels of carotene and its deposit in the skin.
Carotenoids are deposited in the intercellular lipid containing spaces in stratum corneum.

Thick epidermal layers and regions of increased sweating like nasolabial folds, palms, knees and soles bear increased deposits and show greater color change.
Carotenoderma differs from yellow color due to bilirubin in not showing coloration of white of eyes.
Primary carotenoderma yellow color usually disappears after the reduction in intake of carotenoids.

Secondary carotenoderma

Usually a underlying disease condition causes increase in serum levels of carotene and secondary carotenoderma discoloration, though the carotene intake is normal.
Kidney malfunction or dysfunction is usually associated with decreased excretion of carotenoids and hypercarotenemia and color change.

Impaired conversion of carotenoids to retinol is seen in diabetes mellitus and hypothyroidism. The associated increase in serum lipids as seen in diabetes mellitus, nephrotic syndrome and hypothyroidism causes yellow skin color and secondary carotenoderma.
In Anorexia nervosa, a self-imposed starvation, diets may be rich in carotene.
Liver disease also leads to yellow color change due to poor utilization and breakdown of carotene resulting in its increased serum levels.

Yellow skin color due to medicines

The use of certain medicines in the treatment of diseases causes yellow coloration.
Tyrosine kinase inhibitors (TKIs) are used in the treatment of various cancers.
Sunitinib (a TKI) used in the cancer therapy is associated with many adverse events and yellow color changes of the epidermal layers.
Color changes start after a week of treatment and with the continuation of the treatment, color intensification has been noticed.

The sclerae and mucous membranes are spared of the color change and on the discontinuation of medicine resolves the coloration.
Probably the excretion of the chemical via the epidermis causes this coloration.
Another TKI, sorafenib also causes a diffuse yellow discoloration of the skin.

Tuesday, December 7

Bluish discoloration of skin can be due to cyanosis, Raynaud's Syndrome, methemoglobinemia, Mongolian spot or argyria. The skin color is determined by epidermal pigments and the colors of blood and pigments carried by the blood.

Bluish skin discoloration and cyanosis

Deoxygenated hemoglobin equal to 2.5 g/dL or greater in blood causes bluish coloration called cyanosis.
Though the deoxygenated blood appears dark red, there are certain optical principles involved in its giving of different coloration.
Tissues are low in oxygen in cyanosis and are filled up with dark red deoxygenated blood in place of oxygenated bright red blood.

Darker blood generates shift in optical effects leading to bluish skin discoloration.
Cyanosis can be due to many health problems and notable among them are all types of blood circulatory problems, all types of ventilatory problems and extreme cold.

Toxins such as cyanide interfere with oxygenation of blood and cause cyanosis.

In cyanosis two types of conditions are observed namely central and peripheral cyanosis.
Circulatory or breathing problems cause reduced oxygenation of blood in the lungs and slowing down the oxygen circulation and the skin turns bluish. This is a serious situation can lead to lung or heart failure.
In the peripheral cyanosis only the extremities become bluish due to inadequate blood oxygen supply. This can be corrected by increasing the oxygenated blood supply.

Raynaud's Phenomenon is a vasospastic disorder in which blood vessels in fingers and toes spasm, leading to vasoconstriction.
Raynaud's Phenomenon causes bluish color changes in the toes and fingers and their necrosis if unattended.

Raynaud's Phenomenon occurs in sensitized persons as an exaggeration of vasomotor response to emotion or cold leading to bluish discoloration of skin.

In Raynaud's Phenomenon the sympathetic nervous system is hyperactivated affecting the peripheral blood vessels and their extreme vasoconstriction leading to tissue hypoxia.
Recurrent attacks can cause tissue damage, ulceration, gangrene and necrosis.
Shifting to a warm room and keeping fingers in warm water may relieve the symptoms and restore blood circulation.
Persons prone to attacks of Raynaud's Phenomenon are advised to keep themselves warm and if necessary use vasodilatory drugs under the advice of physician.

Methemoglobinemia is a blood disorder wherein, methemoglobin, an oxidised form of hemoglobin is present in levels above normal condition.
In methemoglobinemia, due to oxidative stress the oxygen carrying ferrous ion of hemoglobin molecule is oxidized to ferric state.
This is results in conversion of hemoglobin to methemoglobin which does not bind oxygen.
If the levels of methemoglobin are high in blood bluish chocolate-brown color is imparted to blood.

Methemoglobinemia impedes normal oxygen transport resulting in tissue hypoxia and bluish skin.
Methemoglobinemia may be congenital with autosomal recessive inheritance pattern.
Since congenital methemoglobinemia is recessive, there is a chance of inheritance in the offspring only if both the parents carry the gene.
Patients with impaired production of NADH (the essential cofactor for diaphorase I) with the resultant pyruvate kinase deficiency have risk of getting methemoglobinemia and bluish skin.

Methemoglobinemia is acquired in people exposed to exogenous oxidizing drugs and chemicals.
Antibiotics like dapsone, sulphonamides and trimethoprim can give rise to increased methemoglobin levels and methemoglobinemia.
Certain local anaesthetics (prilocaine and articaine), chlorates, bromates, metoclopramide, nitrates and aniline dyes can also cause methemoglobinemia.
Methemoglobinemia disorder can be treated with oxygen supplementation and administration of intravenous methylene blue 1% solution.

Mongolian spot is a congenital birthmark, which is flat, benign and harmless; it is sometimes mistaken as an injury or bruise during childbirth.
Mongolian spot exclusively involves skin and is due to melanocytes (melanin producing cells) embedded deep in the dermis.
Mongolian spot results from melanocytes entrapment in the dermis during their embryonic development.

Mongolian spot is usually a bluish skin and with irregular shape and wavy borders.
Mongolian spot can appear as multiple skin discoloration spots usually on the shoulders, flanks, lower back and the buttocks.
Mongolian spot is highly prevalent in East Asians, East Africans, Polynesians and Turkic people. As the child with Mongolian spot grows, the spot fades and disappears by puberty.

Argyria is condition wherein irreversible bluish or bluish-grey skin discoloration is caused by exposure to silver dust, silver compound and elemental silver.
Silver gets accumulated in the body and the dermis on chronic exposure. On exposure to sunlight these particles in the skin darken giving a dark discoloration.
Generalized argyria occurs when silver containing compounds are ingested and the whole body gives bluish discoloration.

Localized argyria occurs due to continuous contact with silver and its compounds.
Argyria is a harmless cosmetic problem which can be socially debilitating and mildly disfiguring.
Though generally believed to be irreversible, avoidance of sun exposure and laser therapy appears to give good results.

Sunday, December 5

Reddish skin discoloration (Erythema) is the result of increased blood flow (hyperemia) of the capillaries in the lower dermal layers.

Bruises, certain infections and injuries can give rise to purpura, a reddish coloration due to bleeding underneath the epidermis.

Erythema - reddish skin discoloration

Erythema is hyperaemia of the dermis, wherein there is increased blood flow in capillaries in the lower layers.
Erythema usually has medical implications and occurs with any inflammation, injury or infection.

The cause of erythema in 30-50% of incidences can be unclear and unknown.
There is usually temperature elevation at the site of erythema due to engorgement of blood vessels with oxygenated blood.
On finger pressure, erythema disappears whereas in purpura the reddish color persists.
Fall in atmospheric pressure can also induce erythema.

Purpura and purple or reddish discoloration

Purpura is the appearance of purple or reddish color caused by bleeding underneath.
Purpura does not blanch on applying finger pressure while erythema disappears.
Purpura can result due to injuries and bruises, infections, cutaneous small-vessel vasculitis, foods, hereditary disorders and drug reactions.
In bruise the capillaries and sometimes venules are damaged due to injury allowing blood to seep beneath the dermis and into surrounding interstitial tissues.

In typhus infection dull reddish rash appears on the middle of body and spreads.
Meningitis caused by meningococcal bacteria may be accompanied by a characteristic rash.
Inflammation of small blood vessels (cutaneous small-vessel vasculitis) is clinically characterized by purpura.
Food-induced purpura may result from ingestion of food containing Escherichia coli, benzoates or tartrazine dye.

Allergic reactions to certain drugs can cause extensive purpura.
Purpura can occur due to hereditary blood coagulation disorders as in the case of hemophilia or von Willebrand's disease.
In most cases of purpura there is initially crimson coloration, which turns purple and then blue due to breakdown of blood cells.

Reddish skin coloration and carbon monoxide poisoning

Carbon monoxide is a poisonous gas formed by burning of carbon materials under low oxygen conditions when there is not sufficient oxygen to produce carbon dioxide.
This gas may get produced in running car engine in a closed garage or by burning wood or operating stove in a small closed room.
When this gas is inhaled in larger quantities carbon monoxide poisoning occurs which is highly visible on the victims as Reddish coloration.

Carbon monoxide is highly reactive with blood hemoglobin and forms carboxyhemoglobin.
Carboxyhemoglobin at concentrations above 30% appears bright crimson and the color intensifies with increase in concentrations.
Though at these concentrations it can be fatal, many survivors of lower exposure show apart from many debilitating effects show reddish coloration.